The name Sweeney, though closely associated with Ireland, is of Scottish origin, derived from the Gaelic Mac Suibhne meaning "son of Suibhne". The Gaelic personal name Suibhne was originally a byname meaning "pleasant" or "well-disposed" but was also used as am an equivalent to the unrelated Old Norse personal name Sveinn, meaning "boy", "servant". 

The family moved from Scotland around the time of Robert the Bruce where they settled in Donegal and subsequently split into three main clans: Mac Suibhne Fánad , Mac Suibhne na d’Tuath and Mac Suibhne Boghaineach

Current research identifies progenitor of our line of the Dynan Sweeney family as being Michael Sweeney of Tipperary. It is his daughter Margaret Sweeney who immigrates to Austrlia in 1883.

My Dynan ancestry goes back 5 generations and biographies exist for some members as indicated by links

• Michael Sweeney married Cecily Houlihan
  • Margaret Cecilia Sweeney married James Joseph Dynan  
    • Margaret Dynan 1890 - 1974 married John Joseph Darrough
      • Mary Agnes Darrough 1823 - 1999 married Esmond Earl Jessop
        • My mother